CELA3B (chymotrypsin-like elastase family, member 3B) is a specific human protease synthesised by the acinar cells. It is a serine endopeptidase, a specific type of protease that has the amino acid serine at its active site.CELA3B is stable, unaffected by exogenous pancreatic enzyme treatment, and correlates well with stimulated pancreatic function . It is unique in its ability to hydrolyze elastin, a fibrous and insoluble protein in connective tissue.